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Acta Crystallogr Sect E Struct Rep Online. 2009 June 1; 65(Pt 6): o1269–o1270.
Published online 2009 May 14. doi:  10.1107/S1600536809017127
PMCID: PMC2969617

N-[4-Acetyl-5-(2-methylprop-1-enyl)-5-(2-p-tolyl­prop­yl)-4,5-dihydro-1,3,4-thia­diazol-2-yl]acetamide

Abstract

The title heterocyclic compound, C20H27N3O2S, was synthesized from 2-(4-methyl­cyclo­hex-3-en­yl)-6-methyl­hepta-2,5-dien-4-one, which was isolated from the essential oil Cedrus atlantica. The thia­diazole ring is essentially planar [maximum deviation 0.006 (2) Å] and it forms a dihedral angle of 18.08 (9)° with the benzene ring. The dihedral angle between the thia­diazole ring and the acetamide plane is 7.62 (10)°. In the crystal, mol­ecules are linked into chains running along the c axis by inter­molecular N—H(...)O hydrogen bonds.

Related literature

For the biological activity of 1,3,4-thia­diazole derivatives, see: Demirbas et al. (2005 [triangle]); Holla et al. (2002 [triangle]); Kritsanida et al. (2002 [triangle]); Nizamuddin et al. (1999 [triangle]); Sun et al. (1999 [triangle]); Udupi et al. (2000 [triangle]). For the synthesis, see: Beatriz et al. (2002 [triangle]); Sakthivel et al. (2008 [triangle]). For related structures, see: Loughzail et al. (2009 [triangle]); Tebaa et al. (2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1269-scheme1.jpg

Experimental

Crystal data

  • C20H27N3O2S
  • M r = 373.51
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1269-efi1.jpg
  • a = 10.855 (2) Å
  • b = 14.193 (2) Å
  • c = 12.854 (4) Å
  • β = 90.955 (11)°
  • V = 1980.1 (8) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.18 mm−1
  • T = 100 K
  • 0.28 × 0.17 × 0.12 mm

Data collection

  • Bruker X8 APEX CCD area-detector diffractometer
  • Absorption correction: none
  • 7884 measured reflections
  • 4030 independent reflections
  • 3365 reflections with I > 2σ(I)
  • R int = 0.032

Refinement

  • R[F 2 > 2σ(F 2)] = 0.044
  • wR(F 2) = 0.094
  • S = 1.10
  • 4030 reflections
  • 249 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.24 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: SAINT-Plus (Bruker, 2005 [triangle]); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXS97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809017127/ci2797sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809017127/ci2797Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank Professor J. C. Daran for fruitful discussions.

supplementary crystallographic information

Comment

1,3,4-Thiadiazole derivatives possess antimicrobial (Demirbas et al., 2005) and antiviral (Kritsanida et al., 2002) activities. They are also known for their broad-spectrum of biological activities such as antibacterial (Sun et al., 1999), anti-inflammatory (Udupi et al., 2000) and herbicidal (Nizamuddin et al., 1999). In addition, [1,3,4]thiadiazoles exhibit various biological activities possibly due to the presence of the ═ N—C—S moiety (Holla et al., 2002). In view of these findings and in continuation to our previous work on the synthesis of [1,3,4]thiadiazoles, we report herein the hemisynthesis of N-[4-acetyl-5-isobutenyl-5-(2-p-tolylpropyl)-4,5-dihydro-1,3,4-thiadiazol-2-yl]acetamide, (I), through chemical modification of 2-(4-methylcyclohex-3-enyl)-6-methylhepta-2,5-dien-4-one, which is isolated from Cedrus Atlantica essential oil. Thus, aromatization of this later, followed by condensation with thiosemicarbazide (Beatriz et al., 2002; Sakthivel et al., 2008) ending with treatment of acetic anhydride in the presence of pyridine yielded the diasterioisomers in high stereoselectivity.

The molecular structure of (I) is shown in Fig. 1. The geometric parameters (bond lengths and angles) are very similar to those observed in previously reported structures (Loughzail et al.,2009; Tebaa et al.,2009). The thiadiazole ring system is essentially planar and it forms a dihedral angle of 18.08 (9)° with the benzene ring.

In the crystal structure, molecules are linked into chains (Fig. 2) running along the c axis by intermolecular N—H···O hydrogen bonds (Table 1) involving the carbonyl and the acetamide groups.

Experimental

A mixture of 2-(4-methylcyclohex-3-enyl)-6-methylhepta-2,5-dien-4-one (0.5 g, 2.3 mmol) and Pd/C (10%) was heated at 423 K for 12 h. The product obtained was treated with equimolecular quantity of thiosemicarbazide and several drops of HCl were added. The reactional mixture was heated at reflux in ethanol for 5 h and then evaporated under reduced pressure and the residue obtained was purified on silica gel column using hexane–ethyl acetate (96:4) as an eluent. 0.25 mmol of the thiosemicarbazone obtained was dissolved in 2.5 ml of pyridine and 2.5 ml of acetic anhydride. The mixture was heated on a water bath for 1.5 h. The resulting residue was concentrated in vacuo and chromatographied on silica gel column with hexane–ethyl acetate (92:8) as an eluent. Suitable crystals were obtained by evaporation of an ethyl acetate solution at 277 K.

Refinement

Atoms H2 and H9 were located in a difference map and refined freely. The remaining H atoms were positioned geometrically and refined as riding, with C—H = 0.93 Å (aromatic), 0.96 Å (methyl), 0.97 Å (methylene), 0.98 Å (methine), and with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(Cmethyl).

Figures

Fig. 1.
Molecular structure of the title compound, with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii.
Fig. 2.
Partial packing view showing the N—H···O hydrogen bonds (dashed lines) and the formation of a chain along the c axis. H atoms not involved in hydrogen bonding have been omitted for clarity.

Crystal data

C20H27N3O2SF(000) = 800
Mr = 373.51Dx = 1.253 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 8068 reflections
a = 10.855 (2) Åθ = 2.8–26.4°
b = 14.193 (2) ŵ = 0.18 mm1
c = 12.854 (4) ÅT = 100 K
β = 90.955 (11)°Prism, colourless
V = 1980.1 (8) Å30.28 × 0.17 × 0.12 mm
Z = 4

Data collection

Bruker X8 APEX CCD area-detector diffractometer3365 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.032
graphiteθmax = 26.4°, θmin = 2.8°
[var phi] and ω scansh = 0→13
7884 measured reflectionsk = −17→17
4030 independent reflectionsl = −16→16

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.094H atoms treated by a mixture of independent and constrained refinement
S = 1.10w = 1/[σ2(Fo2) + (0.0257P)2 + 1.5568P] where P = (Fo2 + 2Fc2)/3
4030 reflections(Δ/σ)max = 0.001
249 parametersΔρmax = 0.24 e Å3
0 restraintsΔρmin = −0.20 e Å3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
H20.357 (2)0.0915 (17)0.0811 (19)0.039 (7)*
H90.5323 (18)0.1563 (13)0.5491 (16)0.018 (5)*
C1'0.04998 (19)0.36320 (14)0.44410 (16)0.0263 (4)
H1'0.04730.41820.48330.032*
C2'0.10902 (18)0.28480 (14)0.48503 (15)0.0231 (4)
H2'0.14420.28790.55140.028*
C20.37116 (16)0.09545 (13)0.23153 (13)0.0180 (4)
C3'0.11662 (17)0.20141 (13)0.42843 (14)0.0188 (4)
C30.35748 (17)−0.04166 (13)0.11768 (14)0.0204 (4)
C40.33879 (19)−0.07060 (14)0.00610 (14)0.0252 (4)
H400.3814−0.1287−0.00610.038*
H410.3706−0.0225−0.03860.038*
H420.2524−0.0790−0.00830.038*
C4'0.05884 (17)0.19924 (14)0.33050 (14)0.0216 (4)
H4'0.06110.14420.29130.026*
C50.41102 (17)0.13772 (12)0.42180 (14)0.0178 (4)
C5'−0.00180 (17)0.27755 (14)0.29079 (15)0.0234 (4)
H5'−0.04080.27370.22600.028*
C60.31344 (17)0.12846 (13)0.50691 (13)0.0185 (4)
H600.33700.07590.55120.022*
H610.31760.18480.54950.022*
C6'−0.00551 (18)0.36170 (14)0.34573 (16)0.0247 (4)
C70.17835 (17)0.11399 (13)0.47324 (14)0.0191 (4)
H70.17520.06440.42030.023*
C7'−0.0625 (2)0.44905 (15)0.29915 (17)0.0326 (5)
H70'−0.00040.48480.26440.049*
H71'−0.09740.48660.35330.049*
H72'−0.12600.43150.25000.049*
C80.10620 (18)0.07994 (13)0.56829 (14)0.0227 (4)
H800.14030.02150.59280.034*
H810.02130.07080.54870.034*
H820.11200.12630.62260.034*
C90.53585 (18)0.15303 (13)0.47409 (14)0.0200 (4)
C100.64558 (18)0.16273 (13)0.43130 (15)0.0226 (4)
C110.67035 (19)0.16274 (15)0.31623 (16)0.0286 (5)
H1110.73020.11510.30090.043*
H1120.70130.22330.29610.043*
H1130.59530.14980.27840.043*
C120.75806 (19)0.17719 (15)0.49976 (17)0.0304 (5)
H1210.79820.23480.48070.046*
H1220.81380.12540.49110.046*
H1230.73390.18070.57120.046*
C410.37297 (17)0.30457 (13)0.37021 (13)0.0177 (4)
C420.33714 (19)0.37167 (13)0.28539 (14)0.0231 (4)
H4200.39910.37150.23300.035*
H4210.32960.43400.31370.035*
H4220.25970.35270.25500.035*
N10.35903 (15)0.05391 (11)0.13421 (12)0.0192 (3)
N30.35840 (14)0.18471 (10)0.24065 (11)0.0183 (3)
N40.38013 (14)0.21218 (10)0.34384 (11)0.0174 (3)
O10.36850 (13)−0.09778 (9)0.18908 (10)0.0256 (3)
O20.39419 (12)0.32905 (9)0.46085 (9)0.0213 (3)
S10.40785 (4)0.02872 (3)0.34223 (3)0.01914 (12)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C1'0.0305 (11)0.0224 (10)0.0261 (10)0.0034 (8)0.0050 (8)−0.0035 (8)
C2'0.0251 (10)0.0248 (10)0.0195 (9)0.0012 (8)0.0007 (8)−0.0015 (8)
C20.0184 (9)0.0205 (9)0.0153 (9)0.0010 (7)0.0019 (7)0.0011 (7)
C3'0.0175 (9)0.0199 (9)0.0192 (9)−0.0004 (7)0.0020 (7)0.0011 (7)
C30.0198 (9)0.0198 (9)0.0215 (10)0.0000 (8)0.0010 (7)−0.0005 (7)
C40.0334 (11)0.0220 (10)0.0201 (10)0.0008 (8)−0.0041 (8)−0.0041 (8)
C4'0.0212 (10)0.0228 (9)0.0207 (9)−0.0018 (8)0.0007 (7)−0.0010 (8)
C50.0221 (9)0.0169 (9)0.0144 (8)0.0007 (7)0.0003 (7)0.0003 (7)
C5'0.0206 (10)0.0304 (10)0.0192 (9)−0.0002 (8)0.0002 (8)0.0043 (8)
C60.0239 (10)0.0187 (9)0.0128 (8)0.0013 (8)−0.0008 (7)0.0012 (7)
C6'0.0196 (10)0.0272 (10)0.0276 (10)0.0032 (8)0.0058 (8)0.0068 (8)
C70.0231 (10)0.0181 (9)0.0160 (9)−0.0001 (7)0.0011 (7)−0.0020 (7)
C7'0.0328 (12)0.0314 (11)0.0338 (12)0.0119 (9)0.0082 (9)0.0077 (9)
C80.0248 (10)0.0216 (9)0.0216 (10)−0.0014 (8)0.0009 (8)0.0000 (8)
C90.0245 (10)0.0197 (9)0.0157 (9)0.0011 (7)−0.0032 (7)0.0018 (7)
C100.0253 (10)0.0171 (9)0.0254 (10)0.0020 (8)−0.0015 (8)0.0013 (7)
C110.0258 (11)0.0285 (11)0.0316 (11)−0.0001 (9)0.0064 (9)−0.0002 (9)
C120.0229 (11)0.0271 (11)0.0410 (12)0.0019 (9)−0.0029 (9)−0.0013 (9)
C410.0193 (9)0.0187 (9)0.0153 (9)−0.0014 (7)0.0009 (7)−0.0003 (7)
C420.0332 (11)0.0183 (9)0.0176 (9)0.0004 (8)−0.0029 (8)−0.0003 (7)
N10.0274 (9)0.0185 (8)0.0117 (7)0.0001 (7)0.0000 (6)−0.0010 (6)
N30.0230 (8)0.0188 (8)0.0130 (7)0.0003 (6)−0.0009 (6)−0.0019 (6)
N40.0240 (8)0.0174 (7)0.0107 (7)0.0021 (6)−0.0006 (6)0.0014 (6)
O10.0358 (8)0.0201 (7)0.0208 (7)0.0013 (6)0.0010 (6)0.0016 (6)
O20.0277 (7)0.0211 (7)0.0149 (6)0.0000 (6)−0.0011 (5)−0.0019 (5)
S10.0254 (2)0.0175 (2)0.0145 (2)0.00277 (19)0.00084 (17)0.00137 (18)

Geometric parameters (Å, °)

C1'—C2'1.384 (3)C6'—C7'1.505 (3)
C1'—C6'1.392 (3)C7—C81.540 (3)
C1'—H1'0.93C7—H70.98
C2'—C3'1.392 (3)C7'—H70'0.96
C2'—H2'0.93C7'—H71'0.96
C2—N31.280 (2)C7'—H72'0.96
C2—N11.387 (2)C8—H800.96
C2—S11.7497 (18)C8—H810.96
C3'—C4'1.397 (3)C8—H820.96
C3'—C71.519 (2)C9—C101.327 (3)
C3—O11.219 (2)C9—H90.97 (2)
C3—N11.373 (2)C10—C121.507 (3)
C3—C41.502 (3)C10—C111.508 (3)
C4—H400.96C11—H1110.96
C4—H410.96C11—H1120.96
C4—H420.96C11—H1130.96
C4'—C5'1.385 (3)C12—H1210.96
C4'—H4'0.93C12—H1220.96
C5—N41.491 (2)C12—H1230.96
C5—C91.518 (3)C41—O21.234 (2)
C5—C61.541 (2)C41—N41.357 (2)
C5—S11.8545 (18)C41—C421.494 (2)
C5'—C6'1.388 (3)C42—H4200.96
C5'—H5'0.93C42—H4210.96
C6—C71.536 (3)C42—H4220.96
C6—H600.97N1—H20.87 (2)
C6—H610.97N3—N41.399 (2)
C2'—C1'—C6'121.60 (18)C6'—C7'—H70'109.5
C2'—C1'—H1'119.2C6'—C7'—H71'109.5
C6'—C1'—H1'119.2H70'—C7'—H71'109.5
C1'—C2'—C3'121.06 (18)C6'—C7'—H72'109.5
C1'—C2'—H2'119.5H70'—C7'—H72'109.5
C3'—C2'—H2'119.5H71'—C7'—H72'109.5
N3—C2—N1119.63 (16)C7—C8—H80109.5
N3—C2—S1119.00 (14)C7—C8—H81109.5
N1—C2—S1121.35 (14)H80—C8—H81109.5
C2'—C3'—C4'117.38 (17)C7—C8—H82109.5
C2'—C3'—C7121.72 (16)H80—C8—H82109.5
C4'—C3'—C7120.80 (16)H81—C8—H82109.5
O1—C3—N1121.87 (17)C10—C9—C5129.19 (17)
O1—C3—C4123.36 (17)C10—C9—H9117.4 (12)
N1—C3—C4114.76 (16)C5—C9—H9113.5 (12)
C3—C4—H40109.5C9—C10—C12119.73 (18)
C3—C4—H41109.5C9—C10—C11125.62 (18)
H40—C4—H41109.5C12—C10—C11114.63 (17)
C3—C4—H42109.5C10—C11—H111109.5
H40—C4—H42109.5C10—C11—H112109.5
H41—C4—H42109.5H111—C11—H112109.5
C5'—C4'—C3'121.18 (18)C10—C11—H113109.5
C5'—C4'—H4'119.4H111—C11—H113109.5
C3'—C4'—H4'119.4H112—C11—H113109.5
N4—C5—C9112.66 (15)C10—C12—H121109.5
N4—C5—C6112.84 (14)C10—C12—H122109.5
C9—C5—C6108.48 (15)H121—C12—H122109.5
N4—C5—S1102.63 (11)C10—C12—H123109.5
C9—C5—S1111.83 (13)H121—C12—H123109.5
C6—C5—S1108.29 (12)H122—C12—H123109.5
C4'—C5'—C6'121.37 (18)O2—C41—N4119.83 (16)
C4'—C5'—H5'119.3O2—C41—C42123.49 (16)
C6'—C5'—H5'119.3N4—C41—C42116.67 (15)
C7—C6—C5118.41 (15)C41—C42—H420109.5
C7—C6—H60107.7C41—C42—H421109.5
C5—C6—H60107.7H420—C42—H421109.5
C7—C6—H61107.7C41—C42—H422109.5
C5—C6—H61107.7H420—C42—H422109.5
H60—C6—H61107.1H421—C42—H422109.5
C5'—C6'—C1'117.35 (18)C3—N1—C2124.06 (16)
C5'—C6'—C7'121.43 (18)C3—N1—H2119.1 (16)
C1'—C6'—C7'121.17 (19)C2—N1—H2116.7 (16)
C3'—C7—C6114.25 (15)C2—N3—N4110.24 (14)
C3'—C7—C8109.29 (15)C41—N4—N3119.79 (14)
C6—C7—C8108.32 (15)C41—N4—C5122.03 (14)
C3'—C7—H7108.3N3—N4—C5118.18 (14)
C6—C7—H7108.3C2—S1—C589.94 (8)
C8—C7—H7108.3
C6'—C1'—C2'—C3'0.9 (3)O1—C3—N1—C2−1.0 (3)
C1'—C2'—C3'—C4'−2.1 (3)C4—C3—N1—C2177.88 (17)
C1'—C2'—C3'—C7−178.47 (17)N3—C2—N1—C3−172.52 (18)
C2'—C3'—C4'—C5'1.0 (3)S1—C2—N1—C39.3 (3)
C7—C3'—C4'—C5'177.45 (17)N1—C2—N3—N4−177.12 (15)
C3'—C4'—C5'—C6'1.3 (3)S1—C2—N3—N41.1 (2)
N4—C5—C6—C753.5 (2)O2—C41—N4—N3−178.76 (15)
C9—C5—C6—C7179.04 (15)C42—C41—N4—N32.1 (2)
S1—C5—C6—C7−59.41 (18)O2—C41—N4—C51.1 (3)
C4'—C5'—C6'—C1'−2.5 (3)C42—C41—N4—C5−178.05 (16)
C4'—C5'—C6'—C7'175.03 (18)C2—N3—N4—C41179.12 (16)
C2'—C1'—C6'—C5'1.4 (3)C2—N3—N4—C5−0.7 (2)
C2'—C1'—C6'—C7'−176.10 (19)C9—C5—N4—C41−59.4 (2)
C2'—C3'—C7—C6−57.9 (2)C6—C5—N4—C4163.9 (2)
C4'—C3'—C7—C6125.84 (18)S1—C5—N4—C41−179.78 (14)
C2'—C3'—C7—C863.6 (2)C9—C5—N4—N3120.51 (17)
C4'—C3'—C7—C8−112.64 (19)C6—C5—N4—N3−116.23 (16)
C5—C6—C7—C3'−73.3 (2)S1—C5—N4—N30.08 (18)
C5—C6—C7—C8164.63 (15)N3—C2—S1—C5−0.96 (16)
N4—C5—C9—C10−55.8 (3)N1—C2—S1—C5177.27 (16)
C6—C5—C9—C10178.55 (19)N4—C5—S1—C20.41 (12)
S1—C5—C9—C1059.2 (2)C9—C5—S1—C2−120.59 (14)
C5—C9—C10—C12−179.85 (17)C6—C5—S1—C2119.95 (13)
C5—C9—C10—C111.5 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H2···O2i0.87 (2)1.96 (2)2.811 (2)167 (2)

Symmetry codes: (i) x, −y+1/2, z−1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CI2797).

References

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